2010年4月14日，青海玉树发生强烈地震。地震后运送救灾物

更新 2022-09-03
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2010年4月14日，青海玉树发生强烈地震。地震后运送救灾物资的飞机对灾区投放物
品（如图所示），物品在空中匀速下落的过程中，其动能和重力势能的变化是（）

A．动能增加，重力势能增加

B．动能不变，重力势能增加

C．动能不变，重力势能减小

D．动能减少，重力势能减少

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